Stock line indicator



April 20, 1943.

A. E. HANDY STOCK LINE INDICATOR Filed Dec. 31, 1942 3 Sheets-Sheet 1 m INVENTOQ Fuel I wwm ATTORNEY A ril 20, 1943.

STOCK LINE INDICATOR Filed Dec. 31, 1942 :s Sheets-Sheet 2 FIGZ Z4 56.9

WWI/07111111111010, 30 m I "5 0,,

INVE NTO BY "577M754? I H ATTONEY A. E. HANDY r 2,316,955 I April 20, 1943.

A. E. HANDY 2,316,955

STOCK LINE INDICATOR Filed Dec. 31, 1942 3 Sheets-Sheet 3 BY 7 III 151 ATTORNEY Patented Apr. 20, 1943 STOCK LINE INDICATOR Arthur Edward Handy, Lynbrook, N. Y., assignor to Otis Elevator Company, New York, N. Y., a corporation of New Jersey Application December 31, 1942, Serial No. 470,902

9 Claims.

The invention relates to stock line recorders for blast furnaces.

Blast furnace installations are provided with stock line recording mechanism for indicating the height of the stock in the furnace. The usual arrangement is to provide one or more rods which extend downwardly from the top of the furnace onto the top of the stock. Each rod is connected by a hoisting rope to the hoisting drum of operating mechanism. Connections are also made to indicating mechanism which registers the position of the bottom of the rod in the furnace. The operating mechanism is controlled to lift the rod before a charge is dumped into the furnace and not to lower the rod back onto the charge until after the top of the furnace has been closed. There is advantage in allowing the rod to follow the downward movement of the stock as this causes the indicating mechanism to register the height of the stock between charges. It is also of advantage to know the rate at which the furnace is digesting the charge as this shows whether the furnace is functioning properly. I

One object of the invention is to provide mechanism for indicating the movementof the top of the stock in the'furnace.

Another object of the invention is to provide mechanism for indicating both the movement of the top of the stock and the height of the stock in the furnace. v

The invention involves operating the indicating mechanism from the hoisting drum and operating the hoisting drum in a manner which allows the rod to move with the stock at all times between charges.

In carrying out the invention in accordance with the arrangementwhich will be described, the hoisting. rope for the rod is wound. on a hoisting drum which in turn is mounted on an operating shaft so as to be able to rotate with respect thereto. This operating shaft is driven by a motor. An arm secured to the shaft engages an abutment on the drum to effect rotation of the drum to lift the rod. When the rod uponbeing raised reaches its upper limit of. travel further rotation of the drum is stopped. The abutment however is yieldable, to' enable continued rotative movement of the operatingshaft. This movement operates switching mechanism to bring the. motor to a stop. In lowering the rod the abutment is held against the arm by the weight of the rod as the operating shaft is rotated in the opposite direction by the motor. Resilient means is provided between thearm and the drumwhich acts to prevent further rotative. movement of the drum after the rod in lowering reaches the top of the stock and to prevent any slack developing in the hoisting rope while the rod is engaging the stock. Continued rotativemovement of the operating shaft after the drum is stopped moves the arm away from the abutment and operates switching mechanism to bring the motor to a stop. As the stock line shifts in the furnace, the drum is rotated by the resilient means to move the abutment farther from the arm in case of a rise of the stock line and is rotated by the weight of the rod to move the abutment toward the arm in case of lowering of the stock line. When a certain point is reached in the movement of the abutment toward the arm, switching mechanism is operated to cause restarting of the motor to cause the .arm to follow the drum.

The indicating mechanism is driven from the drum. This mechanism is arranged to indicate any movement of the stock, preferably in fractions of an inch, and also the distance of the stock line from the. top of the furnace in feet. With the above described arrangement of operating mechanism, the position of the drum is always in exact accordance withthe position of the rod. Therefore the indicating mechanism is in exact synchronism with therod so that the movement and the height of the stock are correctlyindicated at all times.

Features and advantages of the invention will be seen from the above statements as well as fromthe description which follows and. the appended claims. e

In the drawings: Figure 1 isya simplified schematic representation of a blast furnace installation embodying the invention; i Figure 2 is a somewhat schematic representation of the operating mechanism for a stock level indicating rod;

. Figure-3 is a side view, with parts in section, of the operating mechanism for the rod;

. Figure 4 is a View taken along the line 4-4 of Figure 3 with parts omitted;

Figure 5 is a detail taken along the line '55 of Figure 4; V Figure 6 is a-detail of switching mechanism taken along the line 6--6 of Figure 3;

, Figure 7 is a side .viewof the switching mechanism shown in Figure 6;

Figure; 8 is aischematic representation of the indicating mechanism; and

Figure 9 is an across'the line simplified wiring diagram of the circuits. for controllingthe operating motorJfor the rod.

' vide indication at two sides of the furnace. This For a general understanding of the invention, reference may be had to Figure 1. The blast furnace II is provided at the top with a hopper 2 for receiving the stock from the skip buckets. Upon the stock being dumped onto the hopper it 5 falls on the small bell l3. The small bell in turn dumps the stock onto the large bell It. When the specified number of loads have been dumped onto the large bell the large bell is opened dumping the charge into the furnace. The small bell I3 is connected by a hollow rod I6 to one end of a lever l'f. At its opposite end lever carries a counterweight [8 of sufficient mass to counterbalance the weight of the bell and therod plus the weight of the load of material resting on the bell. Similarly large bell I4 is connected to a lever by a rod 2| which extends through hollow rod l6. Lever 2!! is likewise provided with a counterweight 22 which counterbalances. the weight of the bell and the rod as well as the weight of material resting on the bell. The op-. erating mechanism for the bells is not shown.

The mechanism for recording the stock line of the furnace. is illustrated as arranged to prois effected by providing two rods and operating mechanism for each rod. Each rod 25 extends downwardly through the top of the furnace and is provided at its lower end with a plate 24 rest ing on the top of the stock. The upper end of the rod is suspended by a hoisting rope 2B which passes over idler pulleys 2! and 28 and thence downwardly to the hoisting drum 30. The rope is helically wound on the drum and has its other end secured thereto. The hoisting drum is rotatably mounted on operating shaft 3! and is operatively connected to the shaft through the intermediary of an operating arm 32 secured to the shaft. This shaft is driven through reduction gearing 33 by an operating motor 34. An electromechanical brake 35 is provided for stopping and holding the motor. A stop motion device 36 is operated by the shaft at the opposite end thereof to control the motor at the limits of travel of the rod. The indicating mechanism 3? is driven through-a system of Selsyn motors, one designated 38 being driven by the hoisting drum and the other, not shown in Figure 1, being located at the indicating. mechanism and connected by wires in conduit 4!] to motor 38 Referring now to Figures 3 and 4, the gear case 45 for the reduction gearing 33 is mounted on a base 45. The operating shaft 3| for the drum extends from the gear case and has a roller bearing 4'! on the end thereof. This bearing'is held between a' shoulder 48 formed on the shaft and a nut 50 secured to thethreaded end 5| of the shaft. The drum 30 is mounted on the bearing 41 Soas to be freeto rotate with respect to the shaft. Oil retaining and protective caps 52 and 53 are provided for the bearing and are 7 secured to the drum as by bolts 54.- A driving .tween the drum and the gear casing. The-hub is secured to the shaft as by a key 56 so that the arm is rotated with theshaft. A roller 59-isprovided on the outer end of the arm. A 'compres- "=0 sion spring 5! is provided through. which the operating arm acts to effect the liftingof the rod.

This spring is mounted on a cylindrical guide 58 extending from a bracket 60 securedltoa boss 6| on the drum as by screwsgBZ, seeFigure 5. Within this guide extends a bolt 63 having an abutment B4 on the end thereof adjacent the operating arm. The spring extends between a spring seat formed on this abutment and the bracket 60 and is maintained therebetween in a state of compression by nuts 65 outside the bracket on the threaded end 66 of the bolt. The amount of compression of the spring is such that no movement of the rod within the guide 58 takes place during the lifting of the rod prior to the rod reaching its upper limit of movement. When the rod reaches its upper limit it engages a stop indicated at 61. in Figure 1 which brings the drum to. a stop. Continued movement of the operating shaft '3| compresses spring 5'1 during which movement switching mechanism is operated as will be described later to bring the motor to a stop.

of drum 3!] and is provided to prevent slack developing in the hoisting rope for the rod when the rod is in position on top of the stock in the furnace. The far end I2 of the spring as viewed from the gear case is hooked over a lug 13 formed on thedrum and retained in position by a retaining plate 14 secured to the lug as by bolts '15.

The spring extends helically clockwise around the hub and its other endis hooked over a'lug 16 on operating arm 32. The strength of the spring and number of turns are such that it may be placed under sufficient tension, as by rotation during assembly of operating arm 32 clockwise as viewed in Figure 4, to maintain the hoisting rope taut but not to lift the rod off the stock. A

stop 11 is secured to the drum to engage the operating arm to limit the possible movement by the torsion spring of the drum with respect to rate at which the shaft 3| is permitted to rotate by. control of the operating motor. Vihen the rod engages thetop of the stock the. drum comes to a stop due to the action of torsion spring 10. Continued rotative movement of shaft 3|, however, moves roller 59 away from abutment 64. During this movement switching mechanism is operated as will be described later to. bring the motor to a stop.

The switching mechanism operated by contin: ued rotative movement of operating shaft 3| after the drum: is stopped iscarried by another arm extending from hub 55. Thismechanism is mounted on a segment 8| on the end of arm80 and comprises. two switches, one designated 82 for causing the stopping 'of'the operating motor when the rod is .stopped at its'upper limit of movement and theother designated 83 for causing the. stopping of the operating' mo'tor when J the 'rod:in' lowering engages the top of the stock. These switches are of. the same construction so that only; one 'ofthem'will be described.

Switch 83. is .shownLinT Figuresrfi and 7. In the arrangement illustrated: thisi switch "comprises a mounting-plate: 85. Secured to this. plate asby screws 'is'a mounting bracket BGof insulating material. having an outwardly extending arm 81. A pair or. contact plates :88 are secured. asby binding screws 9.0{to the 'undersideof arm- 81. Each. plate has 2 a contact; tip .91 secured a the;

A torsion spring H1 is arranged on the hub H a a fulcrum 95 as by screws 96.

end thereof. These contact tips are engaged by contact tips 92 carried by the ends of contact springs 93. These contact springs are carried by a bracket 94 of insulating material secured to The contact springs are bridged by a conductor plate 91 and the conductor plate and springs are secured to bracket 94 as by screws 98. The fulcrum 95 is rotatably mounted on a pivot pin I99 secured to the base 85. v

The contact springs are moved into and out of engagement with the stationary contacts about pin I99 as a pivot by a toggle. An operating member I95 is pivotally mounted on a pin I96 secured to base 85. An L-shaped bracket I9! is pivotally mounted in the lower end of the operating member. A pin I 98 extends upwardly from fulcrum 95 through an aperture. I99 provided in the arm of bracket I91. A compression spring H9 is arranged on pin I98 between the bracket and the fulcrum. The operating member I95 is U-shaped at its upper end, the arms III and II2 thereof being adapted to engage alug II3 formed on the inside of the rim of drum 39 to effect the operation of the toggle. A stop pin H4 is secured to plate 85 to be engaged by stop lugs II 5 and H9 formed on the bottom of the operating member to limit the amount of movement of the toggle. The plate 85 is secured to segment BI by screws II'I. These screws extend into elongated slots H8 in plate 85 to enable the position of the switch to be adjusted with respect to the operating lug II3.

With the switch in the position illustrated in Figure 6, upon the drum being brought to a stop by the rod engaging the top of the stock, continued movement of arm 89 by shaft 3I in a clockwise direction causes arm III to engage lug II3. Further movement results in the toggle being swung to dead center, compressing spring I I9 so that as the toggle moves on past dead center the fulcrum 95 is snapped into its opposite position causing the disengagement of the contact springs from the stationary contacts. Lug II5 engages stop pin II4 to limit the opening movement of the switch. The disengaged position of the contact springs is indicated in dot-dash lines in Figure 6.

During the continued movement of the shaft to effect the opening of switch 83, operating arm 32 is rotated along with arm 89, moving roller 59 away from abutment 64. It is to be noted that considerable clearance exists betweenoperating arm III and lug I I3 in the closed position of the switch. This is to enable arm 89 to have sufficient reverse movement to cause the toggle to be swung back past its dead center and thus effect the closing of the switch before the oper ating roller 59 engages abutment 54. Upon reverse movement of arm 89 to effect the closing of the switch, the other arm II2 of the operating member engages lug II3 to swing the toggle back to and past dead center. Spring III) acts as dead center is passed to snap the fulcrum back to its original position, reclosing theswitch. The operation of switch 82 is effected in .a similar manner and will not be described in detail.

Lugs I29 are formed on arms 32 and 89 and on a third arm I2I. extending from hub 55 for supporting an insulating ring I22. Collector rings I23 are secured to the insulating .ring and are connected through binding screws I24 to the binding screws 99 of switches 92 and 83. Only three collector rings are. illustrated inasmuch as one may. serve .as a com mon feed to each of-the two switches. These collector rings are engaged by brushes I25 mounted on a. bracket I26 secured as by screws I21 to the gear case 45. These brushes are connected to terminal screws I28 through which they are connected to the control system.

Switches 82 and 83 are utilized to cause the stopping of the operating motor 34 for the rod. These switches are illustrated in simplified control circuits for the motor in Figure 9. The armature of the operating motor is designated I35 and its field winding I36. I31 and I38 are control resistances for the operating motor. The electromagnetic control switches for the operating motor are designated generally by letters as follows:

A Accelerating switch RH Rod hoisting switch RL Rod lowering switch These letters are applied to the coils of the switches and with reference numerals appended thereto they are also applied to the contacts of these switches. The release coil of the electromechanical brake 35 is designated BR. GK and CY are contacts on the furnace controller for controlling the sequence of operation of the rod operating mechanism. UL and DL are limit switches provided by stop motion device 36.

In describing the operation of the control system shown in Figure 9, reference may also be had to Figure 2 in which. the mechanism is shownfor the condition with the rod at some intermediate position between its upperlimit and the stock, line of the furnace. Assume that the cycle of operation has reached a point where the'time for opening the large bell to dump a charge onto the furnace drawsnear. Prior to the opening of the large bell, and preferably during the last operation of the small bell,-controller contacts CX close and controller contacts CY open. The closing of contacts CX completes a circuit for the coil of rod hoisting switch RH. This switch operates to separate interlockcontacts EH2, to engage contacts EH3 and EH4 completing a .circuit for armature I35 of the rod operating motor and to engage contacts RHI to complete the circuit for the brake release coil. As a result the brake is released and the rod opera-ting motor starts in operation in a direction to rotate the drum clockwise as viewed in Figure 2, lifting the rod. Initially resistance I3! is in series with the motor armature and resistance I38 by-passesthe motor armature. However, as the motor speeds up the coil of accelerating switch A is energized sufliciently to cause the closing of contacts A2 and the separation of contacts AI.. This removes the by-pass resistance from the motor armature and short circuits the series resistance, bringing the motorup to full speed. As the rod reaches its upper limit of tating at a slow speed moving arm 32 clockwise against the force of spring 51; During this movement operating member I49 of switch 82 engages lug II on the drum toswing the operating toggle to and past dead center to effect the tacts CX open.

. at all times.

opening of switch 82. This breaks the circuit for the coil of rod hoisting switch RH. This switch drops out to break the circuit for the armature of the rod operating motor and for the brake release coil, with the result that the brake is applied bringing the. motor to a stop.

After the charge has been dumped onto the furnace and the large bell has been reclosed, controller contacts CY close and controller coh- The closing of contacts CY completes the circuit for the coil of rod lowering switch RL. This switch operates to separate interlock contacts RLZ, to engage contacts RL3 and RL4 completing the circuit for the armature of the rod operating motor, and to engage contacts RLI to complete the circuit, for the brake release coil'BR. Thus the brake is released and the motor operates in a direction to permit the rod to lower by its own weight. During the initial movement of the motor, operating member I40 engages lug I4I to reclose switch 32. During the lowering of the rod the coil .of ac celerating switch A is short-circuited by contacts RL3 so-that by-pass resistance I38 remains connected across the motor armature and series rc sistance I31 remains in series with the motor ar mature to give the desired speed for lowering the rod. When the rod engages the top of the stock the drum comes to a stop. The motor, however, continues to rotate with the result that operating arm 32 moves roller 59 away from abutment 64. As this Vmovement takes place operating member I engages lug H3 to swing the toggle to and past dead center to effect the opening of switch 83. This breaks the circuit for the coil'of rod lowering switch R-L. This switch drops out to break the circuit for the armature of the rod operating motor and for the brake release coil with the result that the brake is applied to bring the motor to a stop.

As the stock line lowers in the furnace the rod follows it down as the drum is free to rotate. The drum rotates counterclockwise during this movement, and as this movement continues a point is reached where lug II3 engages and moves operating member I05 into'position to reclose switch 83. This effects reoperation of rod lowering switch BL to effect counterclockwise movement of operating shaft 3! with the result that operating member I55 engages lug H3 and causes the reopening of switch 83. This opera tion is repeated as the stock line lowers in the furnace to permit the rod to follow the stock Should the stock line for any reason rise, torsion spring I0 causes clockwise rotative movement of the drum to prevent any slack in the hoisting rope. In effecting this op eration abutment 64 is moved farther away from roller 59 and lug I I3 is moved farther to the right relative to operating member 105. Howev'enthis does not effect the operation of switch 83 by lug I I3 since when the stock line lowers again counterclockwise movement of the drum takes place and a point is reached wher'e lug [3 effects the reclosing of the switch.

"The stock line is usually kept within a certain range in the furnace. However, should the stock line sink below this range the rod follows the stock down until a certain point is reached where down limit switch DL opensto break the circuit for the coil'of rod lowering switch RL to bring the rod operating mechanism to a stop. When the time approaches to dump a charge on the furnace, switch 83 usually will be open. Upon th clbsifig of controller contacts CX to cause the" hoisting of the rod, the init'ial clockwise rotativer'novement of operating shaft 3I causes the C105- ing of switch 83 and upon the engagement of roller 59 with abutment 64 the drum is rotated to lift the rod as above described.

Thus it is seen that the rod follows the stock at all times between charges. The indicating mechanism is driven from the drum 30 and inasmuch as the drum rotates in accordance with movement of the rod the indicating mechanism is in exact accordance with the position of the rod in the furnace.

ure 1 and the other being located with the indicating mechanism on an indicating panel.

The indicating mechanism is indicated schematically in Figure 8. The driven Selsyn motor is designated I50. This motor operates through a clutch device I 5I to rotate shaft I52. On the end of shaft I52 is a pinion I53 which meshes with a gear I54 to form a gear reduction. This gear drives a tubular shaft I55 on the end of which is arranged a pointer I55. This pointer is utilized to indicate the height of the stock in the furnace on a scale I51. Also arranged on shaft 152 is a gear I60 which meshes with a pinion I6I to provide step up gearing. This pinion is on a shaft I62 which extends through tubular shaft I55. On the outer end of shaft IE2 is a pointer I53 which is utilized to show the movement of the stock. Mechanism may also be provided for making a permanent record chart of the stock line throughout the operation of the furnace. This mechanism may be driven from gear I54 by means of a pinion I 65 and is indicated at I56 in Figure 1.

- The scale I5! is laid out in twenty-four equal divisions. The amount of gear reduction pro vided by pinion I53 and gear I54 issuch that for the diameter of drum 30 movement'of the pointer I55 over one division represents one foot of movement of the rod. The division marks are num bered in feet from a zero point which represents the bottom of the larg bell in closed position. Thus the position of the pointer I56 on the scale between charging operations represents the height of the stock in the furnace. The gear I60 and pinion l5l are so chosen that for the diarneter of drum 30 movement of pointer I63 over one division on the scale represents inch of movement of the stock thereby providing a very sensitive indication of the action of the stock in the furnace. Since the hoisting drum follows the movement of the rod, the pointer I6 3 shows both the rise andfall of the stock and all fluctuations. Thus by simply watching the dial the attendant not only is advised of the height of the stock but also as to how the furnace is digesting the stock.

It is the usual practice to allow about two feet of movement of the rod above the bottom of the large bell before the rod engages its stop. Al-

lowance is made for this movement on the dial by the two unnumbered division marks between twenty-one and zero; Should any stretch of the hoisting rope take place the pointer I56 engages stop pin I61 on the scale I57 to bring the pointer to a stop in position two divisions beyond the zero point. The clutch I5I slips during continued movement of motor I50 until the rod engages its stop 61. Thus upon the lowering of the rod back mtoithe furnace the pointer I56 will reach the zero'point on scale'I5I asthe bottom of the rod canes opposite t e" bottom" of the large" bell so The indicating mechanism drive comprises a pair of Selsyn motors, one of; which is driven from the drum as shown in Figthatthe indicating mechanism is maintained in step with the rod.

As many changes could be made in the above construction and many apparently widely different embodiments of this invention could be made without departing from the scope thereof, it is intended that all matter contained in the above description or shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense.

What is claimed is:

1. In a blast furnace installation; a stock level indicating rod; a hoisting drum for said rod; driving mechanism for said drum; means connecting said driving mechanism to said drum for relative rotative movement; and means responsive to relative rotative movement of said driving mechanism and said drum for controlling the operation of said driving mechanism.

2. In a blast furnace installation; a stock level indicating rod; a hoisting drum for said rod; driving mechanism for said drum; means connecting said driving mechanism to said drum for relative rotative movement, said drum being rotated with respect to said driving mechanism by movement of said rod in following said stock while said driving mechanism is stopped; means responsive to such rotative movement upon its reaching a certain amount for causing the operation of said driving mechanism to decrease the amount of relative rotative movement between said driving mechanism and said drum; and means operable upon said relative rotative movement being decreased to a certain amount to cause stopping of said driving mechanism.

3. In a blast furnace installation; a stock level indicating rod; a hoisting drum for said rod; driving mechanism for said drum; means connecting said driving mechanism and said drum for movement in a certain position with respect to each other during lifting of the rod off the stock and lowering it onto the stock but to enable relative rotative movement of either with respect to the other; means responsive to movement of said driving mechanism out of said certain position with respect to said drum after the drum is stopped by the rod reaching its upper limit of travel to cause stopping of said driving mechanism; and means responsive to movement of said driving mechanism away from said certain position with respect to said drum while the rod is engaging the stock to cause the stopping of the driving mechanism, and responsive to the movement of said drum toward said certain position with respect to the driving mechanism by said rod in following the downward movement of said stock to cause movement of said driving mechanism away from said certain position with respect to said drum.

4. In a blast furnace installation; a stock level indicating rod; an operating shaft; a hoisting drum for said rod mounted on said shaft and rotatable with respect thereto; driving mechanism for said shaft; an operating member secured to said shaft; an abutment carried by said drum and held in engagement with said operating member by the weight of said rod upon operation of said driving mechanism to lower the rod; means for stopping rotative movement of said drum when the rod engages the stock, continued operation of said driving mechanism after said drum is stopped moving said operating member away from said abutment; means responsive to said movement of said operating member a certain distance away from said abutment for causing stopping of said driving mechanism and responsive to movement of said abutment to within a certain distance of said operating member by the lowering of said rod to follow the stockto cause restarting of said driving mechanism; and indicating mechanism driven from said 5. In a blast furnace installation; a rod eX tending downwardly into the furnace an operating shaft; a hoisting drum for said rod mountedon said shaft and rotatable with respect thereto; driving mechanism for said shaft; an operating member secured to said shaft; an abutment carried by said drum and engaged by said operating member upon rotation of said shaft in one direc-' tion to cause lifting of said rod and being held in engagement with said operating" member'by the weight of said rod upon rotation of said shaft in the opposite direction tolower the rod; means for preventing slack in said rope when the rod is engaging the stock, continued rotative move ment of said operating shaft in said opposite di' rection when said rod is engaging said stock moving said operating member away from said abutment; means responsive to said movement of said operating member a certain distance away from said abutment for causing stopping of said driving mechanism and responsive to movement of said abutment to within a certain distance of said operating member by rotative movement of said drum by the lowering of said rod to follow the stock to cause restarting of said driving mechanism to rotate said operating member in said opposite direction to follow said drum; and indicating mechanism driven from said drum.

6. In a blast furnace installation; a rod extending downwardly into the furnacepa hoisting rope for said rod; an operating shaft; a hoistingdrum for said rope mounted on said shaft and rotatable with respect thereto; driving mechanismifor said shaft; an operating member secured to said shaft; an abutment carried by said'drum and engaged by said operating member upon rotation of said shaft inone direction to cause lifting of said rod and being held in engagement with said operating member by the weight of said rod upon rotation of said shaft in the opposite direction to lower the rod; means responsive to continued operation of engaging the stock, continued rotative movement of said operating shaft in said opposite direction when said rod is engaging said stock moving said operating member away from said abutment; means responsive to movement of said operating member away from said abutment for causing stopping of said driving mechanism and to rotative movement of said drum by the lowering of said rod to follow the stock to cause restarting of said driving mechanism to rotate said operating member in said opposite direction to follow said drum; and indicating mechanism driven from said drum.

7. In a blast furnace installation; a rod extending downwardly into the furnace for resting on the top of the stock; a stop for limiting the upward movement of said rod; a hoisting rope for said rod; a hoisting drum for said rope; an operating shaft, said drum being mounted on said shaft and being rotatable with respect thereto; a motor for operating said shaft; an operating member secured to said shaft; an abutment carried by said drum and engaged by said operating member to cause lifting of said rod upon rotation of said shaft in one direction and to permit IQWGI, 1 i d? b its wn h up n re ain-r1 o said shaft in the opposite direction, said abutment beingyieldable to permit furtherrotative movement of said shaft in said one direction when the drum is stopped by the rod engagingsaid stop; resilient means connected between said drum and said operating member for preventing slack in said rope when the rod is engaging the stock; means responsive to continued rotative movement of said shaft in said one direction to cause yielding of said abutment and to rotative movement of said shaft in said oppqsite direction while said rod is engaging the stock to move said operating member away from said abutment for causing stopping. of said motor and to rotative movement of said drum by the loweringof aid rod to follow the stock to cause restarting of said motor to rotate Said operating member in said opposite direction to follow said drum; and mechanism drivenfrom said drum for indicating the height of the stock in'the furnace and the movement of said stock in the furnace.

8. In a blast furnace installation; a rod extending downwardly into the-furnace for resting on the top of the stock; a stop for limiting the upward movement of said rod; a hoisting rope for said rod; an operating shaft; a hoisting drum for said rope mounted on said shaft and rotatable with respect thereto; a motor for operating said shaft; a precompressed spring carried by said drum; an operating member secured to said shaft and acting through said spring to cause lifting of said rod upon rotation of said shaft in one direction and to permit lowering of said rod by its own weight upon rotation of said shaft in the opposite direction, said spring yielding when thedrum is stopped by the rod engaging said stop, to permit further rotative movement of said shaft in said one direction; a second spring connected between said drum and said operating member for preventing slack in said rope when the rod is engaging the stock, said second spring acting during rotative movement of said shaft in said opposite direction to stop rotative movement of said drum when said rod engages the top of the stock; switching mechanism operable by continued rotativemovement of said shaft in said one direction after said rod has engaged said stop and by continued rotative movement of said shaft in said opposite direction after said rod has engaged the stock to cause stopping of said motor; an indicati the movement of said stock in the furnace.

annea in dia a ir of wi ters for saidi ial; and

means driven from said drum for causing movement of one of said pointers to indicate the height of the stock in the furnace and for cansing move; ment of the other of said pointers to indicate the movement of said stock in thefurnace.

9. In a blast furnace installation in which the stock is dumped into the furnace from a bell; a rod extending downwardly into the furnace from the top thereof for resting on the top ofthe stock; a stop for limiting the upwardmoven ent of said rod; a hoisting rope for said rod; a hoisting drum for said rope; an operating shaft, said drum being mounted on said shaft and being rotatable with respect thereto; a motor for operating said shaft; an abutment carried by said drum; an operating member secured to said shaft for engaging said abutment to cause lifting of said rod upon rotation of said shaft by said motor in one direction and to permit lowering of said rod by its own Weight upon rotation of said shaft by said motor in the opposite direction; a spring between said abutment and said drum precompr-essed an amount to'prevent further compression thereof during rotation of said shaft in said one direction to lift the rod but to yield when the drum is stopped by the rod engaging said stop to permit further rotative movement of said shaft; switching mechanism operable by continued rotative movement of said shaft in said one direction after said rod has engaged said stop to cause stopping of said motor; a torsion spring on said shaft connected between said drum and said operating member for preventing slack in said rope when the rod is engaging the stock, said torsion spring acting during rotative movement of said shaft in said opposite direction to stop rotative movement of said drum when said rod engages the top of the stock; switching mechanism operable by rotative movement of said shaft in said opposite direction when said rod is engaging the stock to cause stopping of said motor and by rotative movement of said drum by the lowering of saidrod to follow the stock to cause operation of said motor to rotate 7 said operating member to follow said drum; an

indicating dial; a pair of pointers for said dial; and means driven from said drum for causing movement of one of said pointers to. indicate'the height of the stock in the furnace and for causing movement of the other of said pointers to indicate ARTHUR EDWARD HANDY. 

